Carbocyclic adenosine analogs useful as immunosuppressants

ABSTRACT

This invention relates to novel carbocyclic adenosine compounds of the formula (1) ##STR1## wherein the hydroxy substituent on the cyclopentanyl ring is in the CIS configuration relative to the bicyclic substituent, 
     Y 3 , Y 7 , Y 8  and Y 9  are each independently nitrogen or a CH group, 
     Q is NH 2 , halogen or hydrogen, and 
     Z is hydrogen, halogen, or NH 2  ; 
     or a pharmaceutically-acceptable salt thereof, and to their use as immunosuppressants.

This is a continuation-in-part of application Ser. No. 07/748,172,abandoned filed Aug. 23, 1991, which is a continuation-in-part ofapplication Ser. No. 07/582,280, filed Sep. 14, 1990.

FIELD OF THE INVENTION

This invention relates to certain carbocyclic adenosine analogs whichare useful as immunosuppressants.

BACKGROUND OF THE INVENTION

Immunity is concerned with the recognition and disposal of foreignantigenic material which is present in the body. Typically the antigensare in the form of particulate matter (i.e., cells, bacteria, etc.) orlarge protein or polysaccharide molecules which are recognized by theimmune system as being "non-self", i.e., detectably different or foreignfrom the animals own constituents. Potential antigens can be a varietyof substances, often proteins, which are most frequently located on theouter surfaces of cells. For example, potential antigens can be found onpollen grains, tissue grafts, animal parasites, viruses, and bacteria.Once the antigenic material is recognized as "non-self" by the immunesystem, natural (non-specific) and/or adaptive immune responses can beinitiated and maintained by the action of specific immune cells,antibodies and the complement system. Under certain conditions,including in certain disease states, an animal's immune system willrecognize its own constituents as "non-self" and initiate an immuneresponse against "self" material.

An immune response can be carried out by the immune system by means ofnatural or adaptive mechanisms, each of which are composed of bothcell-mediated and humoral elements. Natural mechanisms for immuneresponse refer to those mechanisms involved in essentially non-specificimmune reactions which involve the complement system and myeloid cellsalone, such as macrophages, mast cells and polymorphonuclear leukocytes(PMN), in reacting to certain bacteria, viruses, tissue damage and otherantigens. These natural mechanisms provide what is referred to asnatural immunity. Adaptive mechanisms for immune response refer to thosemechanisms which are mediated by lymphocytes (T and B cells) andantibodies which can respond selectively to thousands of differentmaterials recognized as "non-self". These adaptive mechanisms providewhat is referred to as adaptive immunity and lead to a specific memoryand a permanently altered pattern of response in adaptation to theanimal's own environment. Adaptive immunity can be provided by thelymphocytes and antibodies alone or, more commonly, can be provided bythe interaction of lymphocytes and antibodies with the complement systemand myeloid cells of the natural mechanisms of immunity. The antibodiesprovide the humoral element of the adaptive immune response and theT-cells provide the cell-mediated element of the adaptive immuneresponse.

Natural mechanisms of immune response involve phagocytosis bymacrophages and PMN whereby foreign material or antigen is engulfed anddisposed of by these cells. In addition, macrophages can kill someforeign cells through its cytotoxic effects. The complement system whichis also involved in natural immunity is made up of various peptides andenzymes which can attach to foreign material or antigen and therebypromote phagocytosis by macrophages and PMN, or enable cell lysis orinflammatory effects to take place.

Adaptive mechanisms of immune response involve the actions againstspecific antigens of antibody secreted by B-lymphocytes (or B-cells) aswell as the actions of various T-lymphocytes (or T-cells) on a specificantigen, on B-cells, on other T-cells and on macrophages.

Antibodies, which are responsible for the humoral aspect of adaptiveimmunity, are serum globulins secreted by B-cells with a wide range ofspecificity for different antigens. Antibodies are secreted in responseto the recognition of specific antigens and provide a variety ofprotective responses. Antibodies can bind to and neutralize bacterialtoxins and can bind to the surface of viruses, bacteria, or other cellsrecognized as "non-self" and thus promote phagocytosis by PMN andmacrophages. In addition, antibodies can activate the complement systemwhich further augments the immune response against the specific antigen.

Lymphocytes are small cells found in the blood which circulate from theblood, through the tissues, and back to the blood via the lymph system.There are two major subpopulations of lymphocytes called B-cells andT-cells. B-cells and T-cells are both derived from the same lymphoidstem cell with the B-cells differentiating in the bone marrow and theT-cells differentiating in the thymus. The lymphocytes possess certainrestricted receptors which permit each cell to respond to a specificantigen. This provides the basis for the specificity of the adaptiveimmune response. In addition, lymphocytes have a relatively longlifespan and have the ability to proliferate clonally upon receiving theproper signal. This property provides the basis for the memory aspect ofthe adaptive immune response.

B-cells are the lymphocytes responsible for the humoral aspect ofadaptive immunity. In response to recognition of a specific foreignantigen, a B-cell will secrete a specific antibody which binds to thatspecific antigen. The antibody neutralizes the antigen, in the case oftoxins, or promotes phagocytosis, in the case of other antigens.Antibodies also are involved in the activation of the complement systemwhich further escalates the immune response toward the invading antigen.

T-cells are the lymphocytes responsible for the cell-mediated aspect ofadaptive immunity. There are three major types of T-cells, i.e., theCytotoxic T-cells, Helper T-cells and the Suppressor T-cells. TheCytotoxic T-cells detects and destroys cells infected with a specificvirus antigen. Helper T-cells have a variety of regulatory functions.Helper T-cells, upon identification of a specific antigen, can promoteor enhance an antibody response to the antigen by the appropriate B-celland it can promote or enhance phagocytosis of the antigen bymacrophages. Suppressor T-cells have the effect of suppressing an immuneresponse directed toward a particular antigen.

The cell-mediated immune response is controlled and monitored by theT-cells through a variety of regulatory messenger compounds secreted bythe myeloid cells and the lymphocyte cells. Through the secretion ofthese regulatory messenger compounds, the T-cells can regulate theproliferation and activation of other immune cells such as B-cells,macrophages, PMN and other T-cells. For example, upon binding a foreignantigen, a macrophage or other antigen presenting cell can secreteinterleukin-1 (IL-1) which activates the Helper T-cells. T-cells in turnsecrete certain lymphokines, including interleukin-2 (IL-2) andγ-interferon, each of which have a variety of regulatory effects in thecell-mediated immune response. Lymphokines are a large family ofmolecules produced by T-cells (and sometimes B-cells) including

IL-2, which promotes the clonal proliferation of T-cells;

MAF or macrophage activation factor, which increases many macrophagefunctions including phagocytosis, intracellular killing and secretion ofvarious cytotoxic factors;

NAF or neutrophil activation factor, which increases many functions ofthe PMN including phagocytosis, oxygen radical production, bacterialkilling, enhanced chemotaxis and enhanced cytokine production;

MIF or macrophage migration factor, which by restricting the movement ofmacrophages, concentrates them in the vicinity of the T-cell;

γ-interferon, which is produced by the activated T-cell and is capableof producing a wide range of effects on many cells including inhibitionof virus replication, induction of expression of class IIhistocompatibility molecules allowing these cells to become active inantigen binding and presentation, activation of macrophages, inhibitionof cell growth, induction of differentiation of a number of myeloid celllines.

Activated macrophages and PMNs, which provide an enhanced immuneresponse as part of the cell-mediated adaptive immunity, arecharacterized as having increased production of reactive oxygenintermediates. This increased production of reactive oxygenintermediates, or respiratory burst, is known as "priming". Certainlymphokines, such as γ-interferon, trigger this respiratory burst ofreactive oxygen intermediates in macrophages and PMNs. Thus,lymphokines, such as γ-interferon, which are secreted by the T-cellsprovide an activation of these macrophages and PMNs which results in anenhanced cell-mediated immune response.

The immune response can provide an immediate or a delayed type ofresponse. Delayed-type hypersensitivity is an inflammatory reactionwhich occurs in immune reactive patients within 24-48 hours afterchallenge with antigen and is the result primarily of a cell-mediatedimmune response. In contrast, immediate-type hypersensitivity, such asthat seen in anaphylactic or Arthus reactions, is an inflammatoryreaction which occurs in immune reactive patients within minutes to afew hours after challenge with antigen and is the result primarily ofhumoral or antibody-mediated immune response.

The ability of the immune system, and in particular the cell-mediatedimmune system, to discriminate between "self" and "non-self" antigens isvital to the functioning of the immune system as a specific defenseagainst invading microorganisms. "Non-self" antigens are those antigenson substances in the body which are detectably different or foreign fromthe animals own constituents and "self" antigens are those antigenswhich are not detectably different or foreign from the animals ownconstituents. Although the immune response is a major defense againstforeign substances which can cause disease, it cannot distinguishbetween helpful and harmful foreign substances and destroys both.

There are certain situations, such as with an allogeneic transplant orin "graft versus host" disease, where it would be extremely useful tosuppress the immune response in order to prevent the rejection ofhelpful foreign tissue or organs. Allogeneic tissues and organs aretissues and organs from a genetically different member of the samespecies. "Graft versus host" disease occurs where the transplantedtissue, for example in a bone marrow transplant, contains allogeneicT-cells of the donor which cause an immune response against therecipient's own tissues. Although both humoral and cell-mediated immuneresponses play a role in the rejection of allogeneic tissues and organs,the primary mechanism involved is the cell-mediated immune response.Suppression of the immune response, and in particular, suppression ofcell-mediated immune response, would thus be useful in preventing suchrejection of allograft tissues and organs. For example, cyclosporin A iscurrently used as an immunosuppressive agent in the treatment ofpatients receiving allogeneic transplants and in "graft versus host"disease.

There are times when the individual's immunological response causes moredamage or discomfort than the invading microbes or foreign material, asin the case of allergic reactions. Suppression of the immune response inthese cases would be desirable.

Occasionally, the immunological mechanisms become sensitized to somepart of the individual's own body causing interference with or evendestruction of that part. The ability to distinguish between "self" and"not self" is impaired and the body begins to destroy itself. This canresult in an autoimmune diseases such as rheumatoid arthritis,insulin-dependent diabetes mellitus (which involves the autoimmunedestruction of the β-cells of the islets of Langerhans which areresponsible for the secretion of insulin), certain hemolytic anemias,rheumatic fever, thyroiditis, ulceractive colitis, myestheniagravis,glomerulonephritis, allergic encephalo-myelitis, continuing nerve andliver destruction which sometimes follows viral hepatitis, multiplesclerosis and systemic lupus erythematosus. Some forms of autoimmunitycome about as the result of trauma to an area usually not exposed tolymphocytes such as neural tissue or the lens of the eye. When thetissues in these areas become exposed to lymphocytes, their surfaceproteins can act as antigens and trigger the production of antibodiesand cellular immune responses which then begin to destroy those tissues.Other autoimmune diseases develop after exposure of the individual toantigens which are antigenically similar to, that is cross-react with,the individual's own tissue. Rheumatic fever is an example of this typeof disease in which the antigen of the streptococcal bacterium whichcauses rheumatic fever is cross-reactive with parts of the human heart.The antibodies cannot differentiate between the bacterial antigens andthe heart muscle antigens and cells with either of those antigens can bedestroyed. Suppression of the immune system in these autoimmune diseaseswould be useful in minimizing or eliminating the effects of the disease.Certain of these autoimmune diseases, for example, insulin-dependentdiabetes mellitus, multiple sclerosis and rheumatoid arthritis, arecharacterized as being the result of a cell-mediated autoimmune responseand appear to be due to the action of T-cells [See Sinha et al. Science248, 1380 (1990)]. Others, such as myesthenia gravis and systemic lupuserythematosus, are characterized as being the result of a humoralautoimmune response [Id.].

Suppression of the immune response would thus be useful in the treatmentof patients suffering from autoimmune diseases. More particularly,suppression of cell-mediated immune response would thus be useful in thetreatment of patients suffering from autoimmune diseases due to theaction of T-cells such as insulin-dependent diabetes mellitus, multiplesclerosis and rheumatiod arthritis. Suppression of humoral immuneresponse would be useful in the treatment of patients suffering fromT-cell independent autoimmune diseases such as myestheniagravis andsystemic lupus erythematosus.

SUMMARY OF THE INVENTION

The present invention provides novel compounds of the formula (1)##STR2## wherein the hydroxy substituent on the cyclopentanyl ring is in

the CIS configuration relative to the bicyclic substituent,

Y₃, Y₇, Y₈ and Y₉ are each independently nitrogen or a CH group,

Q is MH₂, halogen or hydrogen, and

Z is hydrogen, halogen, or MH₂ ;

or a pharmaceutically-acceptable salt thereof.

The present invention also provides a method of effectingimmunosuppression, and more specifically, a method of suppressingadaptive immunity, in a patient in need thereof comprising administeringto said patient an effective immunosuppressive amount of a compound offormula (1).

In addition, the present invention provides a pharmaceutical compositioncomprising an effective immunosuppressive amount of a compound offormula (1) in admixture or otherwise in association with one or morepharmaceutically acceptable carriers or excipients.

DETAILED DESCRIPTION OF THE INVENTION

As used herein the term "halogen" refers to monovalent iodine, bromine,chlorine or fluorine radicals, the term "nitrogen" refers to a trivalentnitrogen radical and the term "CH group" refers to a methylidyneradical.

As used herein, the term "pharmaceutically-acceptable salts" refers toacid addition salts of the compounds of formula (1) wherein the toxicityof the compound is not increased compared to the non-salt.Representative examples of pharmaceutically-acceptable salts, which aremade by treating the compounds of formula (1) with the correspondingacids, are: hydrobromide, hydrochloride, sulfuric, phosphoric, nitric,formic acetic propionic, succinic, glycolic, lactic, malic, tartaric,citric ascorbic, α-ketoglutaric, glutamic, aspartic, maleic,hydroxymaleic, pyruvic, phenylacetic, benzoic, para-aminobenzoic,anthranilic, para-hydroxybenzoic, salicylic, para-aminosalicylic,methanesulfonic, ethanesulfonic, hydroxyethanesulfonic,ethylenesulfonic, halobenzenesulfonic, toluenesolfonic,naphthalenesulfonic and sulfanilic acids. The hydrochloride is preferredas the pharmaceutically-acceptable salt of compounds of formula (1).

It is understood that the hydroxy substituent on the cyclopentanyl ringof the compounds of formula (1) have a CIS configuration relative to thebicyclic substituent. It is further understood that these compounds offormula (1) may exist in a variety of stereoisomeric configurations. Ofcourse, the compounds of formula (1) encompass and include both theindividual stereoisomers and racemic mixtures thereof.

A general synthetic procedure for preparing compounds of formula (1)wherein Y₉ is nitrogen is set forth in Scheme A. ##STR3##

In step a, the reactive 4-hydroxy moiety of (1R,4S)-Cis-1-acetoxy-2-cyclopenten-4-ol (2) is blocked with a hydroxyprotecting group (B) to form the corresponding 4-hydroxy-blocked (1R,4S)-Cis-1-acetoxy-2-cyclopenten-4-ol (3). The particular hydroxyprotecting group used can be one of many conventional hydroxy protectinggroups which are well known and appreciated in the art. The selectionand utilization of particular blocking groups are well known to one ofordinary skill in the art. In general, blocking groups should beselected which adequately protect the hydroxy group during subsequentsynthetic steps and which are readily removable under conditions whichwill not cause degradation of the desired product.

Representative examples of suitable hydroxy blocking groups aretetrahydropyranyl, methoxymethyl, t-butyl-dimethylsilyl,methoxyethoxy-methyl, acetoxy and the like. The preferred blocking groupfor the 4-hydroxy moiety of (2) is a 2-tetrahydropyranyl group. Where itis desired to block the 4-hydroxy of (2) with a 2-tetrahydropyranylgroup, (2) can be reacted with 3,4-dihydro-2H-pyran in the presence oftrifluoroacetic acid to yield the corresponding(1R,4S)-Cis-1-acetoxy-4-(2-tetrahydropyranyloxy)-2-cyclopentene.

In step b, the 1-acetoxy group of the 4-hydroxy-blocked (1R,4S)-Cis-1-acetoxy-2-cyclopenten-4-ol (3) is hydrolyzed and the resulting1-hydroxy is derivatized with a suitable leaving group (L) to form thecorresponding 2-cyclopentene derivative (4). The 1-acetoxy group of (3)is first hydrolyzed with a base such as potassium hydroxide, sodiumhydroxide or ammonium hydroxide in methanol or ethanol. The 1-hydroxygroup of the hydrolyzed derivative thus formed is then derivatized witha leaving group (L). The particular leaving group used can be one ofmany conventional leaving groups which are well known and appreciated inthe art. The selection and utilization of particular leaving groups arewell known to one of ordinary skill in the art. In general, the leavinggroup should be selected which adequately facilitates a displacement ofthe leaving group by an appropriate nucleoside base derivative to obtaina product with retention of configuration. Representative examples ofsuitable leaving groups are triflate, brosyl, tosyl, methanesulfonyl andthe like. The preferred leaving group for step b is a methanesulfonylgroup.

For example, where it is desired to convert the 4-hydroxy-blocked (1R,4S)-Cis-1-acetoxy-2-cyclopenten-4-ol (3) to the corresponding4-hydroxy-blocked (1R, 4S)-Cis-1-methanesulfonyloxy-2-cyclopenten-4-ol,(3) can be hydrolyzed with KOH in ethanol and the resulting free alcoholcan then be isolated and converted to the corresponding4-hydroxy-blocked (1R, 4S)-Cis-1-methanesulfonyloxy-2-cyclopenten-4-olby treatment with methanesulfonyl chloride in the presence oftriethylamine.

In step c, the 2-cyclopentene derivative (4) bearing a leaving group inthe 1-position and a blocked hydroxy group in the 4-position, issubjected to a displacement by the desired nucleoside base (wherein Y₉is nitrogen) to give the corresponding 3-hydroxy blocked carbocyclicnucleoside analog (5) with retention of configuration. For example,where it is desired to convert a 4-hydroxy-blocked (1R,4S)-Cis-1-methanesulfonyloxy-2-cyclopentene-4-ol to the corresponding3-hydroxy-blocked (1R,3S)-Cis-1-(9-adenyl)-4-cyclopenten-3-ol, themethanesulfonyloxy derivative can be treated with adenine in thepresence of sodium hydride.

In step d, the 3-hydroxy blocked carbocyclic nucleoside analog (5) isde-blocked according to standard procedures and techniques well knownand appreciated in the art to give the corresponding carbocyclicnucleoside analog (6). For example, where the 3-hydroxy is blocked witha 2-tetrahydropyranyl group, the 3-hydroxy blocking group can be removedby treatment with acid, such as hydrochloric acid.

In step e, the carbocyclic nucleoside analog (6) is converted to thecorresponding carbocyclic adenosine analog (1a) by catalytichydrogenation, such as by treatment with hydrogen in the presence ofPtO₂.

Alternatively, compounds of formula (1) wherein Y₉ is nitrogen can beprepared according to the following shortened version of Scheme A. Thereactive 4-hydroxy moiety of (1S,4R)-Cis-1-acetoxy-2-cyclopenten-4-olcan be derivatized with a suitable leaving group (L) as described forstep b of Scheme A. The most preferred leaving group for thisalternative scheme is a mesylate group. The thus formed 2-cyclopentenederivative bearing an acetoxy group in the 1-position and a leavinggroup such as a mesylate group in the 4-position is then subjected to adisplacement by the desired nucleoside base (wherein Y₉ is nitrogen) togive the corresponding 3-hydroxy blocked carbocyclic nucleoside analog(5) as described for step c of Scheme A. The compounds of formula (1)wherein Y₉ is nitrogen are then prepared according to steps d and e ofScheme A.

The following example presents a typical synthesis as described byScheme A. This example is understood to be illustrative only and is notintended to limit the scope of the invention in any way. As used herein,the following terms have the indicated meanings: "g" refers to grams;"mmol" refers to millimoles; "mL" refers to milliliters; "DMF" refers todimethylformamide; "° C." refers to degrees Celsius; "mg" refers tomilligrams; "N" refers to the normality of a solution; "psi" refers topounds per square inch; "THF" refers to tetrahydrofuran.

EXAMPLE 1 (1S,3R)-Cis-1-(9-adenyl)-3-hydroxycyclopentane hydrochloride

Step a: (1R,4S)-Cis-1-acetoxy-4-(2-tetrahydropyranyloxy)-2-cyclopentene

To a stirring solution of (1R,4S)-Cis-1-acetoxy-2-cyclopenten-4-ol (1 g,7.0 mmol) in 20 mL of dichloromethane add 3,4-dihydro-2H-pyran (0.6 g,7.1 mmol) and 5 drops of trifluoroacetic acid. Stir the mixture for 24hours. Dilute the mixture with 50 mL of dichloromethane and extract withsaturated sodium bicarbonate and then brine. Dry the organic layer oversodium sulfate. Remove the solvent under vacuum to yield the titlecompound (1.58 g).

Step b:(1R,4S)-Cis-1-methanesulfonyloxy-4-(2-tetrahydropyranyloxy)-2-cyclopentene

Dissolve (1R,4S)-Cis-1-acetoxy-4-(2-tetrahydropyranyloxy)-2-cyclopentene(3.0 g, 13 mmol) in 50 mL of absolute ethanol. To this solution addpotassium hydroxide (0.8 g, 14 mmol) and allow the mixture to stir for 3hours. Concentrate the mixture and apply to a silica gel column (10 g)eluting with ethyl acetate/hexane (1:1). Remove the solvent to yield(1R,4S)-Cis-4-(2-tetrahydropyranyloxy)-2-cyclopenten-1-ol as a colorlessoil (2.38 g).

Dissolve (1R,4S)-Cis-4-(2-tetrahydropyranyloxy)-2-cyclopenten-1-ol (1.2g, 6.6 mmol) in 25 mL of dichloromethane and to this solution addmethanesulfonyl chloride (1.13 g, 9.9 mmol) and triethylamine (0.93 g,9.2 mmol). Stir the reaction for 45 minutes, then extract the reactionmixture with water, brine, and then dry the organic layer over sodiumsulfate. Concentrate the solution to yield the title compound (1.62 g,94% yield) as a yellow oil.

Step c:(1R,3S)-Cis-1-(9-adenyl)-3-(2-tetrahydropyranyloxy)-4-cyclopentene

Add sodium hydride (80%, 0.57 g, 19.8 mmol) to a stirring suspension ofadenine (2.67 g, 19.8 mmol) in 100 mL of DMF at 60° C. After stirringfor 3 hours at 60° C., add(1R,4S)-Cis-1-methanesulfonyloxy-4-(2-tetrahydropyranyloxy)-2-cyclopentene(1.62 g, 6.2 mmol) and continue stirring at 60° C. for 1 hour. Cool thereaction mixture to room temperature and stir overnight. The next day,heat the reaction mixture to 60° C. for 6 hours and then allow to coolto room temperature overnight. Remove the DMF under vacuum and take theresidue up in stirring dichloromethane and water. Remove the organiclayer, extract it with brine and then dry it over sodium sulfate. Removethe solvent under vacuum and dissolve the residue in dichloromethane.Apply the solution to a silica gel column (10 g) eluting withdichloromethane/ethanol (19:1) to yield the title compound (500 mg,26.7% yield).

Step d: (1R,3S)-Cis-1-(9-adenyl)-3-hydroxy-4-cyclopentene hydrochloride

Dissolve(1R,3S)-Cis-1-(9-adenyl)-3-(2-tetrahydropyranyloxy)-4-cyclopentene (0.5g, 1.7 mmol) in 50 mL of distilled water and 1.5 mL of 6N hydrochloricacid. Stir the mixture for 12 hours at room temperature and thenconcentrate to dryness under vacuum. Take the residue up in ethanol withenough ammonium hydroxide to effect a solution, and then add an equalvolume of dichloromethane (ammonium chloride precipitates). Apply themixture to a silica gel column (50 g, 70-230 mesh) eluting withdichloromethane/methanol (4:1) and recovering the title compound in 40mL fractions. Combine and concentrate the fractions containing purematerial to dryness. Dissolve the residue in ethanol and add enough 6NHCl to adjust the pH to 1. Concentrate the solution to dryness to yieldthe title compound (230 mg, 62% yield).

Step e: (1S,3R)-Cis-1-(9-adenyl)-3-hydroxycyclopentane hydrochloride

Dissolve (1R,3S)-Cis-1-(9-adenyl)-3-hydroxy-4-cyclopentene hydrochloride(230 mg, 0.99 mmol) in 25 mL methanol and 75 mL of distilled water. Addplatinum (IV) oxide (50 mg) and hydrogenate the mixture under 30 psi ofhydrogen for 3.5 hours. Filter the mixture through a pad of celite andconcentrate the filtrate to dryness. Dissolve the product in methanol,apply the solution to 20 g of silica gel and elute withdichloromethane:methanol (9:1). Concentrate the fractions containingproduct to dryness and dissolve the residue in methanol. Adjust the pHto 1 with 6N HCl. Concentrate this material to dryness to give the titlecompound (210 mg, 83% yield).

[α]₃₆₅ =+24.4° (methanol, 1.0 mg/mL).

H¹ -NMR(DMSO/TMS) δ=8.7(s,1H), 8.5(s,1H), 5.02(m,1H), 4.3(m,1H),2.4-1.8(m,6H).

The following compounds can be prepared by procedures analogous to thosedescribed above for Example 1 using readily available startingmaterials:

(1S,3R)-Cis-1-[9-(3-deazaadenyl)]-3-hydroxycyclopentane hydrochloride

(1S,3R)-Cis-1-[9-(7-deazaadenyl)]-3-hydroxycyclopentane hydrochloride

(1S,3R)-Cis-1-[9-purinyl]-3-hydroxycyclopentane hydrochloride

(1S,3R)-Cis-1-[9-(8-azaadenyl)]-3-hydroxycyclopentane hydrochloride

(1S,3R)-Cis-1-[9-(2-aminopurinyl)]-3-hydroxycyclopentane hydrochloride

(1S,3R)-Cis-1-[9-(2,6-diaminopurinyl)]-3-hydroxycyclopentanehydrochloride

(1S,3R)-Cis-1-[9-(2-amino-6-chloropurinyl)]-3-hydroxycyclopentanehydrochloride.

The starting materials for the synthetic scheme described above,including (1R, 4S)-Cis-1-acetoxy-2-cyclopenten-4-ol, adenine,7-deazaadenine, purine, 8-azaadenine, 2-aminopurine, 2,6-diaminopurineand 2-amino-6-chloropurine, are readily available or can be madeaccording to conventional procedures and techniques well known andappreciated in the art.

A general synthetic procedure for preparing compounds of formula (1)wherein Y₈ and Y₉ are each a CH group is set forth in Scheme B. ##STR4##

In step a, the 2-cyclopentene derivative (4) is reacted with the sodiumanion of methyl methylsulfinylmethyl sulfide to yield the corresponding1-substituted derivative (7).

In step b, the sodium anion of (7) is reacted with the appropriatepyrimidine or pyridine derivative, such as5-amino-4,6-dichloropyrimidine, followed by hydrolysis to give thecorresponding ketone derivative (8).

In step c, the ketone derivative (8) is converted to the correspondingenol ether (9) by reacting (8) with the appropriate Wittig reagent, suchas φ₃ P═CH₂ OCH₃ [methoxymethyl triphenylphosphylidine chloride], in thepresence of n-butyllithium.

In step d, the enolate (9) is cyclized in the presence of acid, such asHCl, and the 3-hydroxy blocking group is removed according to standardtechniques well known and appreciated in the art, to give the6-substituted carbocyclic nucleoside analog (10).

In step e, the 6-substituted carbocyclic nucleoside analog (10) ishydrogenated as described in Scheme A, step e, to yield the6-substituted nucleoside derivative (1b). Where the 6-substitutedcarbocyclic nucleoside analog (10) bears a chlorine in the 6-position,the 6-chloro derivative can be converted to the 6-amino or 6-hydrogenderivative according to standard techniques well known and appreciatedin the art.

The following example presents a typical synthesis as described byScheme B. This example is understood to be illustrative only and is notintended to limit the scope of the invention in any way.

EXAMPLE 2 (1S,3R)-Cis-1-[9-(9-deazaadenyl)]3-hydroxycyclopentanehydrochloride

Step a:(1R,4S)-Cis-4-t-butyldimethylsilyloxy-1-[methyl(1-methylsulfinyl-1-methylsulfide)]-2-cyclopentene

To a stirring solution of methyl methylsulfinylmethyl sulfide (1.2equivalents) in THF at 0° C. add n-butyl lithium (1.2 equivalents) andallow to stir for 15 minutes. Over a 15 minute period, add dropwise asolution of(1R,4S)-Cis-1-methanesulfonyloxy-4-t-butyldimethylsilyloxy-2-cyclopentene(1 equivalent) in THF and allow to stir for several hours at 0° C. to25° C. Dilute the reaction with water and extract with ethyl acetate ormethylene chloride. Wash the organic layer with water, brine, and dryover sodium sulfate. Concentrate the solution to dryness to yield thetitle compound as a crude product.

Step b:(1R,4S)-Cis-4-t-butyldimethylsilyloxy-1-carbonyl(4-[5-amino-6-chloropyrimidine])]-2-cyclopentene

To a stirring solution of(1R,4S)-Cis-4-t-butyldimethylsilyloxy-1-[methyl(1-methylsulfinyl-1-methylsulfide)]-2-cyclopentene(1 equivalent) in THF at 0° C. add n-butyllithium and continue stirringfor 15 minutes. Over a 15 minute period, add dropwise a solution of5-amino-4,6-dichloropyrimidine (1.1 equivalents) in THF and stir thereaction mixture for 24 hours at room temperature. Dilute the reactionwith water and extract with ethyl acetate or methylene chloride. Washthe organic layer with water, brine, and dry over sodium sulfate.Concentrate the solution to dryness to yield the title compound as acrude product. Purify the title compound using a silica gel columneluting with ethyl acetate/hexane.

Step c:(1R,4S)-Cis-4-t-butyldimethylsilyloxy-1-[ethylene-1-(4-[5-amino-6-chloropyrimidine])-2-methoxy]-2-cyclopentene

To a stirring suspension of methoxymethyl triphenylphosphylidinechloride (1.2 equivalents) in THF at 0° C. add n-butyllithium (1.2equivalents) followed by stirring for 1 hour. Over a 15 minute period,add(1R,4S)-Cis-4-t-butyldimethylsilyloxy-1-[carbonyl(4-[5-amino-6-chloropyrimidine])]-2-cyclopentene(1 equivalent) in THF and stir overnight at 0° C. Concentrate thereaction mixture to dryness and dissolve the residue in diethyl ether.Cool to 0° C. for 1 hour and remove the precipitate (lithium chlorideand triphenylphosphineoxide) by filtration. Concentrate the filtrate toyield the title compound. Purify the title compound using a silica gelcolumn eluting with ethyl acetate/hexane.

Step d: (1R,3S)-Cis-1-[9-(9-deazaadenyl)]-3-hydroxy-4-cyclopenteneHydrochloride

Dissolve(1R,4S)-Cis-4-t-butyldimethylsilyloxy-1-[ethylene-1-(4-[5-amino-6-chloropyrimidine])-2-methoxy]-2-cyclopentenein aqueous methanol and a sufficient amount of 6N HCl and stir at roomtemperature for 4 hours. Neutralize the product with ammonium hydroxideand concentrate the reaction mixture to dryness to yield(1R,3S)-Cis-3-t-butyldimethylsilyloxy-1-[9-(6-chloro-9-deazapurinyl)]-4-cyclopentene.Purify the product using a silica gel column eluting with methylenechloride/ethanol.

Enclose(1R,3S)-Cis-3-t-butyldimethylsilyloxy-1-[9-(6-chloro-9-deazapurinyl)]-4-cyclopentenein a sealed container of methanol and anhydrous ammonia for 24 hoursapplying heat if necessary. Remove the solvent and apply the product toa Dowex 50W™ column eluting with dilute ammonium hydroxide. Concentratethe eluant to dryness, take up in water, make acidic with 6N HCl andstir for 4 hours. Concentrate the solution to dryness to yield the titlecompound.

Step e: (1S,3R)-Cis-1-[9-(9-deazaadenyl)]-3-hydroxycyclopentaneHydrochloride

Dissolve (1R,3S)-Cis-9-[9-(9-deazaadenyl)]-3-hydroxy-4-cyclopenteneHydrochloride in ethanol/water (1:1) and add platinum oxide. React in aParr hydrogenator charged with 35 psi of hydrogen for 12 hours. Removethe catalyst by filtration and concentrate the filtrate to dryness toyield the title compound.

A general synthetic procedure for preparing compounds of formula (1)wherein Y₉ is a CH group and Y₈ is a nitrogen is set forth in Scheme C.##STR5##

In step a, the ketone derivative (8), made as described in Scheme B, isconverted to the corresponding oxime derivative and then cyclized to thecorresponding 8-aza-9-deaza-6-substituted-nucleoside derivative (11) byreacting the oxime with diethylazodicarboxylate (DEAD) andtriphenylphosphine. In addition, the 3-hydroxy blocking group of (8) isremoved according to standard techniques well known and appreciated inthe art.

In step b, the 8-aza-9-deaza-6-substituted-nucleoside derivative (11)can be converted to the corresponding8-aza-9-deaza-6-substituted-carbocyclic adenosine derivative (1c) byhydrogenation as described in Scheme A, step e. Where the8-aza-9-deaza-6-substituted-carbocyclic adenosine derivative (1c) bearsa chlorine in the 6-position, the 6-chloro derivative can be convertedto the 6-amino or 6-hydrogen derivative according to standard techniqueswell known and appreciated in the art.

EXAMPLE 3 (1S,3R)-Cis-1-[9-(8-aza-9-deazaadenyl)]3-hydroxycyclopentanehydrochloride

Step a: (1R,3S)-Cis-1-[9-(8-aza-9-deazaadenyl)]-3-hydroxy-4-cyclopenteneHydrochloride

To a solution of(1S,4S)-Trans-4-t-butyldimethylsilyloxy-1-[carbonyl(4-[5-amino-6-chloropyrimidine])]-2-cyclopentene (1 equivalent) and hydroxylamine hydrochloride (1.2equivalents) in dry methanol add a solution of sodium hydroxide (1.2equivalents). After 2 hours add water and collect and dry the solid thusformed (oxime intermediate). Dissolve the oxime intermediate (1equivalent) in methylene chloride followed by DEAD (1.2 equivalents) andtriphenylphosphine (1.1 equivalents). Allow the mixture to react for 2hours to yield (1R,3S)-Cis-3-t-butyldimethylsilyloxy-1-(9-[8-aza-6-chloro-9-deazapurinyl])-4-cyclopentene.Extract the reaction mixture with water and then brine. Dry the organiclayer over sodium sulfate, concentrate to dryness and add diethyl etherto precipitate out the triphenylphosphine oxide. Remove the precipitateby filtration and purify the product on a silica gel column eluting withethyl acetate/hexane.

Enclose(1R,3S)-Cis-3-t-butyldimethylsilyloxy-1-(9-[8-aza-6-chloro-9-deazapurinyl])-4-cyclopentenein a sealed container of methanol and anhydrous ammonia for 24 hoursapplying heat if necessary. Remove the solvent and apply the produce toa Dowex 50W™ column eluting with dilute ammonium hydroxide. Concentratethe eluant to dryness, take up in water, make acidic with 6N HCl andstir for 4 hours. Concentrate the solution to dryness to yield the titlecompound.

Step b: (1S,3R)-Cis-1-[9-(8-aza-9-deazaadenyl)]-3-hydroxycyclopentaneHydrochloride

Dissolve(1R,3S)-Cis-1-[9-(8-aza-9-deazaadenyl)]-3-hydroxy-4-cyclopenteneHydrochloride in ethanol/water (1:1) and add platinum oxide. React in aParr hydrogenator charged with 35 psi of hydrogen for 12 hours. Removethe catalyst by filtration and concentrate the filtrate to dryness toyield the title compound.

In general, where it is desired to synthesize the corresponding (1R,3S)enantiomer of the compounds of formula (1), procedures similar to thosedescribed above may be followed, except that instead of blocking the4-hydroxy group of the intermediate (2) (so that a leaving group may beattached to the 1-position after hydrolysis of the acetoxy group), anappropriate leaving group is attached at the 4-position leaving the1-acetoxy group or other appropriate blocking group at the 1-position.

For example, a general synthetic procedure for preparing thecorresponding (1R,3S) enantiomers of the compounds of formula (1)wherein Y₉ is nitrogen is set forth in Scheme D. ##STR6##

In step a, the 4-hydroxy moiety of(1R,4S)-Cis-1-acetoxy-2-cyclopenten-4-ol (2) is derivatized with asuitable leaving group (L), by procedures as described in Scheme A, toform the corresponding 2-cyclopentene derivative (4a). Representativeexamples of suitable leaving groups are triflate, brosyl, tosyl,methanesulfonyl and the like. The preferred leaving group is amethanesulfonyl group.

In step b, the 2-cyclopentene derivative (4a) bearing a leaving group inthe 4-position and an acetoxy group in the 1-position, is subjected to adisplacement by the desired nucleoside base (wherein Y₉ is nitrogen) togive the corresponding 1-acetoxy-carbocyclic nucleoside analog (5a) withretention of configuration. This reaction may be carried out asdescribed for the displacement reaction in Scheme A.

In step c, the 1-acetoxy group of the 1-acetoxy-carbocyclic nucleosideanalog (5a) is removed according to standard procedures and techniqueswell known and appreciated in the art to give the correspondingunsaturated carbocyclic nucleoside analog (6a). For example, the1-acetoxy group can be removed by treatment with base, such as potassiumcarbonate.

In step d, the unsaturated carbocyclic nucleoside analog (6a) ishydrogenated according to standard procedures and techniques well knownand appreciated in the art to give the corresponding carbocyclicnucleoside analog (1d).

The following example presents a typical synthesis as described byScheme D. This example is understood to be illustrative only and is notintended to limit the scope of the invention in any way.

EXAMPLE 4 (1R,3S)-Cis-1-(9-adenyl)-3-hydroxy-4-cyclopentanehydrochloride

Step a: (1S,4R)-Cis-1-methanesulfonyloxy-4-acetoxy-2-cyclopentene

Dissolve (1R,4S)-Cis-1-acetoxy-2-cyclopenten-4-ol (1.42 g, 10.0 mmol) in40 mL of dichloromethane. To this solution, add methanesulfonyl chloride(3.72 g, 30.0 mmol) and triethylamine (3.63 g, 30.0 mmol) and allow tostir for 4.5 hours. Extract the mixture sequentially with water and thenbrine. Dry the organic layer over sodium sulfate. Concentrate thesolution to yield the title compound as a yellow oil (2.09 g, 95% yield)which is used immediately in the next reaction.

Step b: (1S,3R)-Cis-1-(9-adenyl)-3-acetoxy-4-cyclopentene

To a stirring suspension of adenine (4.1 g, 30.0 mmol) in 50 mL ofdimethylformamide at 60° C., add sodium hydride (60%, 1.0 g, 30.0 mmol).After the solution has stirred for 3 hours at 60° C., add(1S,4R)-Cis-1-methanesulfonyloxy-4-acetoxy-2-cyclopentene (2.09 g, 9.5mmol) and continue stirring at 60° C. for 16 hours. Remove thedimethylformamide under vacuum and take the residue up in stirringdichloromethane and water. Remove the organic layer, extract with brineand dry the organic layer over sodium sulfate. Remove the solvent undervacuum and dissolve the residue in dichloromethane. Apply the solutionto a silica gel column (40 g) and elute with chloroform/methanol (9:1)to yield the title compound (1.07 g) (33% yield).

Step c: (1S,3R)-Cis-1-(9-adenyl)-3-hydroxy-4-cyclopentene

Dissolve (1S,3R)-Cis-1-(9-adenyl)-3-acetoxy-4-cyclopentene (0.5 g, 1.7mmol) in 25 mL of methanol, then add 3 mL water and then 600 mg K₂ CO₃.Stir the mixture for 1 hour at room temperature, and then concentratethe mixture to dryness under vacuum. Take up the solid in ethanol toprecipitate K₂ CO₃ and filter the mixture. Add an equal amount ofdichloromethane. Apply the mixture to a silica gel column (50 g, 70-230mesh) and elute with dichloromethane/methanol (4:1). Collect fractions(40 mL) and concentrate the fractions containing pure material todryness to yield the title compound (257 mg, 62% yield).

Step d: (1R,3S)-Cis-1-(9-adenyl)-3-hydroxy-4-cyclopentane hydrochloride

Dissolve (1S,3R)-Cis-1-(9-adenyl)-3-hydroxy-4-cyclopentene (50 mg, 0.2mmol) in 5 mL ethanol and 15 mL distilled water. To this solution add 50mg of platinum (IV) oxide and hydrogenate the mixture under 30 psi ofhydrogen gas for 3.5 hours. Filter the mixture through a pad of celiteand concentrate the filtrate to dryness to yield the title compound (41mg, 82% yield).

[α]₃₆₅ =-24° (MeOH, 0.29 mg/mL)

H¹ -NMR(DMSO/TMS) δ=8.7(s,1H), 8.5(s,1H), 5.02(m,1H), 4.3(m,1H),2.4-1.8(m,6H).

The present invention further provides a method of effectingimmunosuppression, and more specifically, a method of suppressingadaptive immunity, in a patient in need thereof comprising administeringto said patient an effective immunosuppressive amount of a compound offormula (1).

As used herein, the term "patient" refers to a warm-blooded animal suchas a mammal which is suffering from a disease, such as an autoimmunedisease or "graft versus host" disease, or is in danger of rejection ofa transplanted allogeneic tissue or organ. It is understood that humans,mice and rats are included within the scope of the term "patient".

Administration of a compound of formula (1) to a patient results in animmunosuppressive effect in the patient. More specifically,administration of a compound of formula (1) to a patient results insuppression of adaptive immunity in the patient. In other words, bytreatment of a patient with a compound of formula (1), the adaptiveimmune response of the patient is inhibited or suppressed over thatpresent in the absence of treatment.

A patient is in need of treatment with an immunosuppressive agent, suchas a compound of formula (1), where the patient is suffering from anautoimmune disease, "graft versus host" disease or in order to preventrejection of transplanted allogeneic tissues or organs. The term"autoimmune disease" refers to those disease states and conditionswherein the immune response of the patient is directed against thepatient's own constituents resulting in an undesirable and oftenterribly debilitating condition.

Patients suffering from autoimmune diseases such as rheumatoidarthritis, endotoxic shock, insulin-dependent diabetes mellitus, certainhemolytic anemias, rheumatic fever, thyroiditis, ulceractive colitis,myestheniagravis, glomerulonephritis, allergic encephalo-myelitis,continuing nerve and liver destruction which sometimes follows viralhepatitis, multiple sclerosis and systemic lupus erythematosus are inneed of treatment with an immunosuppressive agent such as a compound offormula (1). Rheumatoid arthritis, insulin-dependent diabetes mellitusand multiple sclerosis are characterized as being the result of acell-mediated autoimmune response and appear to be due to the action ofT-cells. Myestheniagravis and systemic lupus erythematosus arecharacterized as being the result of a humoral autoimmune response. Assuch, treatment of patients suffering from these diseases byadministration of a compound of formula (1) will be particularlyeffective in preventing further deterioration or worsening of thepatient's condition. Treatment of a patient at an early stage of anautoimmune disease, such as rheumatoid arthritis, insulin-dependentdiabetes mellitus, multiple sclerosis, myestheniagravis or systemiclupus erythematosus, would be particularly effective in preventingfurther deterioration of the disease state into a more seriouscondition. For example, insulin-dependent diabetes mellitus (IDDM) is anautoimmune disease which is believed to result from the autoimmuneresponse directed against the β-cells of the islets of Langerhans whichsecrete insulin. Treatment of a patient suffering from an early stage ofIDDM prior to the complete destruction of the β-cells of the islets ofLangerhans would be particularly useful in preventing furtherprogression of the disease since it would prevent or inhibit furtherdestruction of remaining insulin-secreting β-cells. It is understoodthat treatment of a patient suffering from an early stage of otherautoimmune diseases will also be particularly useful to prevent orinhibit further natural progression of the disease state to more seriousstages.

Patients who have received or who are about to receive an allogeneictissue or organ transplant, such as an allogeneic kidney, liver, heart,skin, bone marrow, are also patients who are in need of prophylactictreatment with an immunosuppressive agent such as a compound of formula(1). An immunosuppressive agent will prevent the adaptiveimmune responseof the donee from rejecting the allogeneic tissue or organ of the donor.Likewise, patients suffering from "graft versus host" disease arepatients who are in need of treatment with an immunosuppressive agentsuch as a compound of formula (1). An immunosuppressive agent willprevent the adaptive immune response of the transplanted tissue or organfrom rejecting the allogeneic tissue or organ of the donee.

Based on standard clinical and laboratory tests and procedures, anattending diagnostician, as a person skilled in the art, can readilyidentify those patients who are in need of treatment with animmunosuppressive agent such as a compound of formula (1).

An effective immunosuppressive amount of a compound of formula (1) isthat amount which is effective, upon single or multiple doseadministration to a patient, in providing an immunosuppressive effector, more particularly, a suppression of adaptive immune response. Animmunosuppressive effect refers to the slowing, interrupting, inhibitingor preventing the further expression of the adaptive immune response.

An effective immunosuppressive amount of a compound of formula (1) canbe readily determined by the attending diagnostician, as one skilled inthe art, by the use of known techniques and by observing resultsobtained under analogous circumstances. In determining the effectiveamount or dose, a number of factors are considered by the attendingdiagnostician, including, but not limited to: the species of mammal; itssize, age, and general health; the specific disease involved; the degreeof or involvement or the severity of the disease; the response of theindividual patient; the particular compound administered; the mode ofadministration; the bioavailability characteristics of the preparationadministered; the dose regimen selected; the use of concomitantmedication; and other relevant circumstances.

An effective immunosuppressive amount of a compound of formula (1) isexpected to vary from about 0.1 milligram per kilogram of body weightper day (rag/kg/day) to about 500 mg/kg/day. Preferred amounts areexpected to vary from about 1 to about 50 mg/kg/day.

In effecting treatment of a patient, a compound of formula (1) can beadministered in any form or mode which makes the compound bioavailablein effective amounts, including oral and parenteral routes. For example,compounds of formula (1) can be administered orally, subcutaneously,intramuscularly, intravenously, transdermally, intranasally, rectally,and the like. Oral administration is generally preferred. One skilled inthe art of preparing formulations can readily select the proper form andmode of administration depending upon the particular characteristics ofthe compound selected the disease state to be treated, the stage of thedisease, and other relevant circumstances.

The compounds can be administered alone or in the form of apharmaceutical composition in combination with pharmaceuticallyacceptable carriers or excipients, the proportion and nature of whichare determined by the solubility and chemical properties of the compoundselected, the chosen route of administration, and standardpharmaceutical practice. The compounds of the invention, while effectivethemselves, may be formulated and administered in the form of theirpharmaceutically acceptable acid addition salts for purposes ofstability, convenience of crystallization, increased solubility and thelike.

In another embodiment, the present invention provides compositionscomprising a compound of formula (1) in admixture or otherwise inassociation with one or more inert carriers. These compositions areuseful, for example, as assay standards, as convenient means of makingbulk shipments, or as pharmaceutical compositions. An assayable amountof a compound of formula (1) is an amount which is readily measurable bystandard assay procedures and techniques as are well known andappreciated by those skilled in the art. Assayable amounts of a compoundof formula (1) will generally vary from about 0.001% to about 75% of thecomposition by weight. Inert carriers can be any material which does notdegrade or otherwise covalently react with a compound of formula (1).Examples of suitable inert carriers are water; aqueous buffers, such asthose which are generally useful in High Performance LiquidChromatography (HPLC) analysis; organic solvents, such as acetonitrile,ethyl acetate, hexane and the like; and pharmaceutically acceptablecarriers or excipients.

More particularly, the present invention provides pharmaceuticalcompositions comprising an effective immunosuppressive amount of acompound of formula (1) in admixture or otherwise in association withone or more pharmaceutically acceptable carriers or excipients.

The pharmaceutical compositions are prepared in a manner well known inthe pharmaceutical art. The carrier or excipient may be a solid,semi-solid, or liquid material which can serve as a vehicle or mediumfor the active ingredient. Suitable carriers or excipients are wellknown in the art. The pharmaceutical composition may be adapted for oralor parenteral use, including topical use, and may be administered to thepatient in the form of tablets, capsules, suppositories, solution,suspensions, or the like.

The compounds of the present invention may be administered orally, forexample, with an inert diluent or with an edible carrier. They may beenclosed in gelatin capsules or compressed into tablets. For the purposeof oral therapeutic administration, the compounds may be incorporatedwith excipients and used in the form of tablets, troches, capsules,elixirs, suspensions, syrups, wafers, chewing gums and the like. Thesepreparations should contain at least 4% of the compound of theinvention, the active ingredient, but may be varied depending upon theparticular form and may conveniently be between 4% to about 70% of theweight of the unit. The amount of the compound present in compositionsis such that a suitable dosage will be obtained. Preferred compositionsand preparations according to the present invention are prepared so thatan oral dosage unit form contains between 5.0-300 milligrams of acompound of the invention.

The tablets, pills, capsules, troches and the like may also contain oneor more of the following adjuvants: binders such as microcrystallinecellulose, gum tragacanth or gelatin; excipients such as starch orlactose, disintegrating agents such as alginic acid, Primogel, cornstarch and the like; lubricants such as magnesium stearate or Sterotex;glidants such as colloidal silicon dioxide; and sweetening agents suchas sucrose or saccharin may be added or a flavoring agent such aspeppermint, methyl salicylate or orange flavoring. When the dosage unitform is a capsule, it may contain, in addition to materials of the abovetype, a liquid carrier such as polyethylene glycol or a fatty oil. Otherdosage unit forms may contain other various materials which modify thephysical form of the dosage unit, for example, as coatings. Thus,tablets or pills may be coated with sugar, shellac, or other entericcoating agents. A syrup may contain, in addition to the presentcompounds, sucrose as a sweetening agent and certain preservatives, dyesand colorings and flavors. Materials used in preparing these variouscompositions should be pharmaceutically pure and non-toxic in theamounts used.

For the purpose of parenteral therapeutic administration, includingtopical administration, the compounds of the present invention may beincorporated into a solution or suspension. These preparations shouldcontain at least 0.1% of a compound of the invention, but may be variedto be between 0.1 and about 50% of the weight thereof. The amount of theinventive compound present in such compositions is such that a suitabledosage will be obtained. Preferred compositions and preparationsaccording to the present invention are prepared so that a parenteraldosage unit contains between 5.0 to 100 milligrams of the compound ofthe invention.

The solutions or suspensions may also include the one or more of thefollowing adjuvants: sterile diluents such as water for injection,saline solution, fixed oils, polyethylene glycols, glycerine, propyleneglycol or other synthetic solvents; antibacterial agents such as benzylalcohol or methyl paraben; antioxidants such as ascorbic acid or sodiumbisulfite; chelating agents such as ethylene diaminetetraacetic acid;buffers such as acetates, citrates or phosphates and agents for theadjustment of tonicity such as sodium chloride or dextrose. Theparenteral preparation can be enclosed in ampules, disposable syringesor multiple dose vials made of glass or plastic.

As with any group of structurally related compounds which possesses aparticular generic utility, certain groups and configurations arepreferred for compounds of formula (1) in their end-use application.Compounds of the formula (1) wherein Y₃ is nitrogen are generallypreferred. Compounds of the formula (1) wherein Y₇ is nitrogen aregenerally preferred. Compounds of the formula (1) wherein Y₈ is a CHgroup are generally preferred. Compounds of the formula (1) wherein Y₉is nitrogen are generally preferred. Furthermore, compounds of theformula (1) wherein Q is MH₂ and Z is hydrogen are generally preferred.

The following specific compounds of formula (1) are especiallypreferred:

(1S,3R) -Cis-1-(9-adenyl)-3-hydroxycyclopentane hydrochloride

(1R,3S)-Cis-1-(9-adenyl)-3-hydroxycyclopentane hydrochloride.

The following studies illustrate the utility of the compounds of formula(1). These studies are understood to be illustrative only and are notintended to limit the scope of the invention in any way. As used hereinthe following terms have the indicated meanings: "μM" refers tomicromolar concentration; "Units" refers to the internationally acceptedmeasurement of protein; "S.D." refers to standard deviation; "ηmol"refers to nanomoles; "ηg" refers to nanograms.

Rat peritoneal macrophages were isolated and grown in cell cultureessentially as described by Edwards et al. [Science 239, 769 (1988)].Macrophages were incubated along with opsonized zymosan (3 mg/mL), whichacts as a particulate stimulus, and recombinant rat γ-interferon(rrIFN-γ) (1000 Units/mL), which acts as an activating lymphokine, inthe presence of various concentrations of(1S,3R)-Cis-1(9-adenyl)-3-hydroxycyclopentane (0 to 1000 μM). The degreeof macrophage priming was measured using the Superoxide Anion (O₂ --)assay as described by Edwards et al. [Science 239, 769 (1988)]. Theresults of this study show that(1S,3R)-Cis-1(9-adenyl)-3-hydroxy-4-cyclopentane effectively inhibitsthe priming of rat macrophages inuro with an IC₅₀ of 2.5 μM.

The rat air pouch model of inflammation was used to obtain rat PMNsusing 250 ηg/pouch of recombinant human interleukin-1 (rHuIL-1) toelicit the cells essentially according to the method of Esser et al.[Internat.J.Tissue ReactionsXI, 291 (1989)]. PMNs were incubated alongwith phorbol myristate acetate (PMA)(200 g/mL), which acts as a solublestimulus, and rrIFN-γ (1000 Units/mL), which acts as a stimulatorylymphokine, or rHuIL-1 (500 Units/mL) , which acts as a stimulatorycytokine, in the presence of various concentrations of(1S,3R)-Cis-1(9-adenyl)-3-hydroxycyclopentane (0 to 1000 μM). The degreeof macrophage priming was measured using the Superoxide Anion (O₂ --)assay as described by Edwards et al. [Science 239, 769 (1988)]. Theresults of this study show that(1S,3R)-Cis-1(9-adenyl)-3-hydroxycyclopentane effectively inhibits therrIFN-γ priming of rat PMN inuro with an IC₅₀ of 0.001 μM andeffectively inhibits the rHuIL-1 priming of rat PMN in vitro with anIC₅₀ of 0.001 μM.

What is claimed is:
 1. A compound of the formula ##STR7## wherein thehydroxy substituent on the cyclopentanyl ring is in the CISconfiguration relative to the bicyclic substituent,Y₃ is nitrogen, Y₇,Y₈ and Y₉ are each independently nitrogen or a CH group, Q is NH₂,halogen or hydrogen, and Z is hydrogen, halogen, or NH₂ ;or apharmaceutically-acceptable salt thereof.
 2. A compound of claim 1wherein the compound is (1S,3R)-Cis-1(9-adenyl)-3-hydroxycyclopentane.3. A compound of claim 1 wherein the compound is(1R,3S)-Cis-1(9-adenyl)-3-hydroxycyclopentane.